Method and device for the encryption and decryption of data

ABSTRACT

Method for the encryption of data as well as a corresponding decryption method are set forth. In order to guarantee a secure transmission of data with relatively little effort, an encryption method is provided in which a key vector with a second length is generated from a secret key information vector with a short length and a public matrix with a size corresponding to the first length times a second length, which is greater than the first size, and in which an encryption vector is formed by means of a first encryption method from a data vector with a third length, which is less than or equal to the second length, and the key vector.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the priority of German Application No. 101 48415.1, filed Sep. 29, 2001, and which is incorporated herein byreference.

FIELD OF THE INVENTION

The invention relates to a method and a device for the encryption aswell as decryption of data and a method of transmission making use ofsuch a method.

BACKGROUND OF THE INVENTION

As a rule, when confidential data are transmitted via insecure channels,the data are encrypted on the transmitter side, the encrypted datatransmitted, and the encrypted data decrypted again by the receiver. Todo this, various encryption or cryptographic methods are known:

The role of traditional cryptographic methods employing, for example,transposition encryption and simpler or more complex substitutions hasnow become practically insignificant because methods of attack aregenerally known for this; therefore, there can be no adequate guaranteeof security against decryption by third parties.

In the so-called secret key methods transmitter and receiver employ asecret code that should not be known to attackers. Block encryption,stream encryption and encryption via hash functions are known in thisrespect. Block encryption methods contain symmetric algorithms thatprocess the original data or the plain text block by block, whereby afixed block size is specified.

Stream encryption methods are symmetric methods that process the plaintext bit by bit or byte by byte, e.g. One-Time-Pad, RC4, SEAL, WAKE,FCSRs. In the One-Time-Pad method the plain text is reproduced by bitvectors of length l, whereby each bit vector is encrypted with a secretkey vector of length p≧1. In this case every data vector of the plaintext is interlinked with the key vector bit by bit by way of XOR so thata bit string of length r is output. Hence, the encrypted text contains asequence of bit vectors with length r and is sent to the receiver. Thereceiver can then link the encryption vectors with the key vector againbit by bit by way of XOR and from this obtain the data vectors of theplain text again. In doing so, the mathematical property of the XORfunction is exploited such that the duplicated XOR linking of a firstBoolean variable with a second Boolean variable leads to the firstBoolean variable again, which means that the XOR link is an inversion initself.

This method of encryption—like other stream encryption methods—is securewhen a sufficiently large key vector is used. In this respect, bitvectors of length, for example, r=65 536 bits are normally used. Highdata rates exceeding 1 MB/s or even 1 GB/s are possible with such secretkey methods.

However, one particular problem is the transmission of the secret keythat the receiver requires to decrypt the information. The transmissionand secure storage of the key is, in cryptographic terms, a weak pointwith regard to attack by third parties, which means that secret keymethods are used only to a limited extent.

Asymmetric methods, also called public key methods, are also known. Inthese methods there is a public key that can be used by anyone toencrypt a plain text and send the encrypted text to the receiver. Thereceiver has a private key with which he can decrypt the encryptedinformation. The private key is known only to the receiver; and when thecode is sufficiently long, the private key also cannot be derived fromthe public key with a feasible computational effort. Examples ofasymmetric methods regarded as secure are, in particular, RSA, Rabin,ElGamal, McEliece, cryptosystems based on elliptical curves andprobabilistic public key encryption. The latter employs random valuesfor the encryption.

The disadvantage of the public key method, especially the probabilisticpublic key method, is the high computational effort required on both thetransmission and the reception side. Data rates of 1 MB/S, e.g. 1024bits—regarded these days as a secure key length—for RSA, are onlypossible at present with special hardware; data rates of 1 GB/s cannotbe achieved with the hardware currently available.

OBJECTS AND SUMMARY OF THE INVENTION

It is an object of the invention to supply improvements as compared tothe state of the art and, in particular, to create methods forencrypting a plain text, decrypting the encrypted text, suitable devicesfor doing this and a method of transmission making use of the encryptionand decryption method according to the invention in which a high levelof security against unauthorized access by third parties is guaranteedbut the computational effort is nonetheless not excessive so that evenhigh data rates are possible and, advantageously, processing in realtime is made possible. In doing so, it should be regarded as anadvantage when the security against unauthorized access is at least ashigh as with the known methods.

This object is achieved by an inventive encryption method for theencryption of data in which a key vector with a long second length isgenerated from a secret key information vector with a short first lengthand a public matrix; and an encryption vector is formed from a datavector with a third length, which is shorter than or equal to the secondlength, and the key vector by means of a first encryption method.

This object is likewise achieved by an inventive decryption method fordecryption of encrypted data, which have been formed by an encryptionmethod according to the invention, in which a key vector with a longsecond length is formed from a key information vector with a short firstlength and a public matrix; and a data vector with the long secondlength is formed from an encryption vector with the long second lengthand the key vector by means of a first decryption method.

This object is achieved by an inventive method for the encryptedtransmission of data from a transmitter to a receiver in which thetransmitter generates encryption vectors from data vectors, a keyinformation vector and a public matrix by way of an inventive encryptionmethod, the encryption vectors and the key information vector are sentto a receiver, and the receiver decrypts the encryption vectors from thepublic matrix and the key information vector by means of an inventivemethod for the decryption of encryption data.

This object is achieved as well by the inventive devices for performingthe inventive encryption and decryption methods according to any of theembodiments of the invention, such as an inventive device for encryptionof data by means of an inventive encryption method, the encryptiondevice including a key calculation device for calculating a key vectorwith a long second length from a key information vector with a shortfirst length and a matrix, and a first encryption device for recordingthe key vector and a data vector with a third length, which is less thanor equal to the long length, and supplying an encryption vector with thelong length.

There is likewise an inventive device for decryption of encrypted databy means of one of the inventive decryption methods, the deviceincluding a key calculation device for calculating the key vector with along second length from a key information vector with a short firstlength and a matrix; and a decryption device for recording an encryptionvector with the long length and the key vector and for supplying a datavector with the long second length.

The object is achieved by a computer program for executing the inventivemethods and controlling the inventive device.

A computer-readable medium is provided that contains instructions forcontrolling a computer system to perform any of the inventive methodsand to control any of the devices.

A concept behind the invention is to encrypt a plain text making use ofa secret key and not to transmit the key itself but instead to send tothe receiver only information of minimum length from which the key canbe generated. For this purpose, the public key available to bothtransmitter and receiver is a table or matrix with p rows and r columns(or vice versa) whose elements are randomly determined single bits.

For encryption, in a first step the transmitter generates the key withthe greater length from this table using the key information andsubsequently applies a first encryption method with the help of the keyobtained in this way. This encryption method can be, in particular,stream encryption, e.g. the One-Time-Pad method, that enables a highencryption speed and a high level of security against decryption withoutknowledge of the key. According to the invention, in order to do thisthe plain text is subdivided into data vectors with a third length thatis less than or equal to the long length and can be encrypted directlyusing the key with the greater length. As a rule, the third lengthadvantageously corresponds to the long length; however, for example,residual bits can also be placed in smaller data vectors or the datavectors filled up correspondingly with zeros. The subdivision of thedata into data vectors and the linking of each one of them with the keyvector can, for example, also be achieved by linking the bit string ofthe data continuously with a bit string from consecutive key vectorswithout individual data vectors being explicitly formed and temporarilystored.

The relatively small amount of key information can in this case beencrypted by means of a secure second encryption method requiringsomewhat more intensive computational effort, e.g. a public key methodsuch as RSA, and transmitted to the receiver. As the key information hasa shorter length than the key used for the first encryption method, thecomputational effort for encrypting and decrypting the key informationis not excessive. The receiver again obtains the key from the keyinformation and the public table and can thus retrieve the plain text byusing a second decryption method.

In the randomly generated table or matrix, pair-by-pair equality and theoccurrence of zero vectors can be excluded as a restrictive criterion inorder to increase the level of security. Furthermore, when generatingthe key information vector a restrictive criterion can be to set thenumber of zeros and ones to be approximately equal, e.g. by stipulatingupper and lower limits for zeros or ones about the middle value (p/2).

According to the invention, compared to a conventional secret key methodthere is a considerable reduction in computational effort because merelythe relatively small amount of key information needs to be transmittedin order to transmit the secret key. The information can therefore beencrypted with a high level of security by using a secure methodinvolving intensive computations. In doing so, for example, keyinformation with 256 bits can be used to identify a key with 65 536bits.

The generation of the key with the long length r from the keyinformation with short length p and the p×r matrix can be achieved, forexample, by the transmitter selecting t integers at random from theintegers 0 to p−1, whereby, for example, t=p/2. The rows in the tablecorresponding to these integers are linked bit by bit by means of XOR toform a bit string r, from which the key vector can be obtained. As analternative to this method, somewhat modified methods are basicallypossible in accordance with the invention, e.g. using the inversefunction on the key vector obtained in this way. The bit vector thatidentifies the t integers is encrypted as a key information vector bythe second encryption method and sent to the receiver.

The calculations for obtaining the key vector from key informationvector and table or matrix can be carried out—at least partly—by meansof hardware in particular by calculating the individual digits of thekey vector by way of suitable hardware circuitry from the digits of thematrix and the key information vector. The XOR linking of data vectorand key vector at the transmitter—or encryption vector and key vector atthe receiver—can also be carried out by suitable hardware to create amethod that can be carried out fast but still guarantee a high level ofsecurity. Consequently, a very secure but slow second encryption methodfor the key information can be combined with the fast, first encryptionmethod for the plain text.

According to the invention the key information can advantageously beencrypted with and transmitted as part of the plain text in an.Consequently, in the first data transmission from transmitter toreceiver merely the key information is encrypted, transmitted andsubsequently decrypted again by means of the second encryption method.In the subsequent encryption method the key information transmittedpreviously in plain text can be used by the receiver to decrypt theencrypted data in order to reduce the effort required to encrypt anddecrypt the key information. In doing so, new key information can beprovided, in particular successively, by the transmitter every time inplain text from which the receiver can obtain new key information ineach case for the decryption of the following encrypted data, whereby ineach case the same public table can be used without having to acceptdrawbacks in terms of security. Therefore, in this preferred furtherdevelopment maximum data rates are possible without having to compromisesecurity.

Relative terms such as up, down, left, right, row, column, height,width, and the like are for convenience only and are not intended to belimiting.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is explained in more detail below by way of a number ofembodiments with the help of the accompanying drawings.

FIG. 1 shows an example of a random matrix for the encryption anddecryption method according to the invention;

FIG. 2 shows the step for generating a key from the matrix and keyinformation;

FIG. 3 shows the step for encrypting the plain text by means of the key;

FIG. 4 shows the data sent to the receiver;

FIG. 5 shows the step for decrypting the encrypted data at the receiver;

FIG. 6 shows the transmission of new key information according to anembodiment of the invention;

FIG. 7 shows a block diagram of a transmitting device and receivingdevice according to an embodiment of the invention; and

FIG. 8 shows a block diagram of a transmitting device and receivingdevice according to a further embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 shows a random matrix M whose elements M_(ij), where i=1 . . .p=6 and j=1 . . . , r=14, are each one bit generated by a random numbergenerator. An exclusion criterion for selecting the matrix can specifythat the column vectors (small matrix vectors) are never equal and, forexample, no zero vectors occur.

According to FIG. 7 a receiver 1 has a key calculation device 2, a firstencryption device 3 and a second encryption device 4. The transmitter 1selects a key information vector SI as a p-digit bit vector. This canagain be carried out using a random number generator; the creation ofthis key information vector corresponds to the selection of t differentrows of the p-row matrix M according to FIG. 2, whereby when selecting arow—according to FIG. 2 the first, third and sixth rows—the respectivedigit of the bit vector SI is set to 1 and the remaining digits to 0.

The key calculation device 2 calculates a 14-digit secret key vector Sas a 14-digit binary number, which is explained in more detail in FIG.2, from the secret six-digit key information vector SI and the public6×14 matrix M. The digits of the 6-digit key information vector SIsignify the rows of the matrix M relevant for determining the key vectorS. The 14-digit row vectors determined in this way are interlinked bitby bit by the XOR function such that the interlinking of an even numberof ones produces a zero at the corresponding digit of the 14-digit keyvector S, and the interlinking of an odd number of ones produces a one.Hence, this calculation corresponds to a matrix multiplication of the6×14 matrix with the 6-digit vector SI to produce the 14-digit vector S,whereby for the multiplication of the elements the AND link is used andfor the addition of the factors formed in this way the XOR function(which corresponds to a half adder).

According to FIG. 7 the key vector S obtained in this way is inputtogether with a data vector D (consisting of components DR and SI₂) oflength r=14 into a first encryption device 3 in which they are combinedthrough a bit-by-bit linking by means of the XOR function to form anr=14-digit encryption vector C. This linking therefore corresponds tothe One-Time-Pad method.

According to FIG. 7 the key information vector SI is further encryptedin a second encryption device 4 using a public key K1, which, forexample, can be taken from an RSA method or another public key method.The key information vector CSI encrypted in this way issubsequently—together with the encryption vector C—relayed by thetransmitter 1 via a transmission channel to the receiver 5. The datathus sent to the receiver 5 are reproduced in FIG. 4, whereby the keyinformation vector is shown without encryption here.

The receiver first uses his private key K2 to decrypt the encrypted keyinformation vector CSI in a second decryption device 6 and forms the keyvector S from the key information vector and the public matrix M in thekey calculation device 7—which can correspond to the key calculationdevice 2. The data vector D (with its components DR and SI₂) is againobtained from the key vector S and the encryption vector C in the firstdecryption device 8 according to the method shown in FIG. 5. Here, ther-digit data vector D is obtained by the bit-by-bit linking of theencryption vector C and the key vector S according to the method shownin FIG. 3 and output, possibly by converting it to a decimal number—inthis case the decimal number 9501.

For simplification, FIG. 6 shows the generation of the encryption vectorC directly from a linking of the data vector D and the relevant rows ofthe matrix M without illustrating the key vector S. According to FIG. 6a second key information vector SI₂ can be sent as part of the datavector D in the plain text data transmitted. The second key informationvector SI₂ can then be used to generate a new—second—key S₂ by means ofthe matrix M in the subsequent encryption method—according to the bottomhalf of FIG. 6—so that in the subsequent method in contrast to FIG. 7 asecond encryption device 4 and second decryption device 6 are no longerrequired.

This is shown in more detail in FIG. 8. The second key informationvector SI₂ transmitted with the first method of FIG. 7 is stored in akey information memory 10 and input into the key calculation device 2for the next encryption process, which calculates a second key S₂ asdescribed above and relays this to the encryption device 3. Furthermore,a third key information vector SI₃ is generated, e.g. by a random numbergenerator, and this is, firstly, stored in the key information memory 10for the next process and, secondly, input into the encryption device 3together with residual data DR as a new data vector D, where a newencryption vector C is calculated and sent to the receiver 5.

The second key information vector SI₂ is read out in the receiver 5 froma key information memory 11, the second key S₂ is calculated in the keycalculation device 7 from the matrix M and SI₂ and fed to the decryptiondevice. The decryption device 8 calculates the data vector D from C andS₂, whereby its residual data DR can be read as plain text and the thirdkey information vector SI₃ is input into the key information memory 11for the next process. The key information memories 10 and 11 can in thiscase be designed, for example, as registers.

This method can be repeated for every data transmission so that the keyvector is altered successively, which makes unauthorized decryption moredifficult at least.

It will be seen that the invention includes at least the following 21features:

1. A method for the encryption of data is provided in which a key vector(S) with a long second length (r) is generated from a secret keyinformation vector (SI) with a short first length (p) and a publicmatrix (M), and an encryption vector (C) is formed from a data vector(D) with a third length (l), which is shorter than or equal to thesecond length (r), and the key vector (S) by means of a first encryptionmethod.

2. Method according to Feature 1, in which the matrix (M), whoseelements (M_(ij)) are randomly generated bits, has a height and width ofthe first and second length (r, p) comprising small matrix vectors (V1)with the short length (p) and large matrix vectors (V2) with the longlength (r).

3. Method according to Feature 1 or 2, in which the small matrix vectors(V1), preferably also the large matrix vectors (V2), are not identicaland not equal to zero.

4. Method according to one of the above Features, in which the keyinformation vector (SI) specifies which of the large matrix vectors (V2)is to be used for determining the key vector (S).

5. Method according to Feature 4, in which the small matrix vectors (V1)are multiplied bit by bit with the key information vector (SI) and thedigits of the key vector (S) are formed from the values created by thesemultiplications by way of an XOR link.

6. Method according to one of the above Features, in which the firstencryption method is a symmetric encryption method, preferably a streamencryption method, in which the elements of the key vector (S) and thedata vector (D) are interlinked.

7. Method according to Feature 6, in which in the first encryptionmethod one element of the encryption vector (C) is determined from oneelement of the key vector (S) and one element of the data vector (D) byway of an XOR link.

8. Method according to one of the above Features, in which the keyinformation vector (SI) is encrypted by means of a second encryptionmethod, preferably an asymmetric encryption method, e.g. an RSA method.

9. Method for decryption of encrypted data, which have been formed by amethod according to one of the above Features, in which a key vector (S)with a long second length (r) is formed from a key information vector(SI) with a short first length (p) and a public matrix (M), and a datavector (D) with the long second length (r) is formed from an encryptionvector (C) with the long second length (r) and the key vector (S) bymeans of a first decryption method.

10. Method according to Feature 9, in which the first decryption methodcorresponds to the first encryption method and contains a link betweenthe elements of the key vector (S) and the encryption vector (C) by wayof an XOR link resulting to the elements of the data vector (D).

11. Method for the encrypted transmission of data from a transmitter (1)to a receiver (5) in which the transmitter (1) generates encryptionvectors (C) from data vectors (D), a key information vector (SI) and apublic matrix (M) by way of a method according to one of the Features1-8, in which the encryption vectors (C) and the key information vector(SI) are sent to a receiver (5), and the receiver (5) decrypts theencryption vectors (C) from the public matrix (M) and the keyinformation vector (SI) by means of a method according to Features 9 or10.

12. Method according to Feature 11, in which the key information vector(SI) is encrypted by the transmitter by means of a public key (K1), e.g.an asymmetric encryption method, and the encrypted key informationvector (CSI) is sent to the receiver (5), and the receiver (5) obtainsthe key information vector (SI) from the encrypted key informationvector (CSI) by means of a private key (K2) from the encrypted keyinformation signals (CSI).

13. Method according to Features 11 or 12, in which the data vectors (D)transmitted contain a second key information vector (SI₂) that is usedto calculate a new key (S) by means of the public matrix (M) in asubsequent encryption method of the transmitter (1) and decryptionmethod of the receiver (5).

14. Device for encryption of data by means of a method according to oneof the Features 1-8 with a key calculation device (2) for calculating akey vector (S) with a long second length (r) from a key informationvector (SI) with a short first length (p) and a matrix (M), and a firstencryption device (3) for recording the key vector (S) and a data vector(D) with a third length (l), which is less than or equal to the longlength (r), and supplying an encryption vector (C) with the long length(r).

15. Device according to Feature 14, in which it has a second encryptiondevice (4) for encrypting the key information vector (SI), preferably bymeans of a public key (K1).

16. Device according to Feature 14 or 15 for executing a methodaccording to Features 6 or 7, in which the first encryption device (3)contains a parallel computation device for the parallel calculation ofthe elements of the key vector (S).

17. Device for decryption of encrypted data by means of a methodaccording to Features 9 or 10, with a key calculation device (7) forcalculating the key vector (S) with a long second length (r) from a keyinformation vector (SI) with a short first length (p) and a matrix (M),and a decryption device (8) for recording an encryption vector (C) withthe long length (r) and the key vector (S) and for supplying a datavector (D) with the long second length (r).

18. Device according to Feature 17, in which it has a second decryptiondevice (6) for recording a encrypted key information vector (CSI) and aprivate key (K2) and for supplying the key information vector (SI).

19. Encryption signal comprising one or more encryption vectors (V)produced by a method according to one of the Features 1-8.

20. Computer program comprising computer-executable instructions forexecuting a method according to one of the Features 1 to 8 or accordingto one of the Features 9 to 10 on a computer.

21. Computer program product or computer-readable medium comprisingcomputer-compatible instructions for carrying out a method according toone of the Features 1 to 8 or according to one of the Features 9 to 10on a computer.

While this invention has been described as having a preferred design, itis understood that it is capable of further modifications, and usesand/or adaptations of the invention and following in general theprinciple of the invention and including such departures from thepresent disclosure as come within the known or customary practice in theart to which the invention pertains, and as may be applied to thecentral features hereinbefore set forth, and fall within the scope ofthe invention or limits of the claims appended hereto.

1. A method for the encryption of data, comprising: a) generating a keyvector with a long second length from a secret key information vectorwith a short first length and a public matrix; and b) forming anencryption vector from a data vector with a third length, which thirdlength is shorter than or equal to the second length, and the key vectorby means of a first encryption method.
 2. Method according to claim 1,wherein: a) the matrix, whose elements are randomly generated bits, hasa height and width of the first and second length, respectively,comprising small matrix vectors with the short length and large matrixvectors with the long length.
 3. Method according to claim 2, wherein:a) the small matrix vectors are not identical and not equal to zero. 4.Method according to claim 3, wherein: a) the key information vectorspecifies which of the large matrix vectors is to be used fordetermining the key vector.
 5. Method according to claim 4, wherein: a)the small matrix vectors are multiplied bit by bit with the keyinformation vector and the digits of the key vector are formed from thevalues created by these multiplications by way of an XOR link.
 6. Methodaccording to claim 1, wherein: a) the first encryption method is asymmetric encryption method in which the elements of the key vector andthe data vector are interlinked.
 7. Method according to claim 6,wherein: a) in the first encryption method one element of the encryptionvector is determined from one element of the key vector and one elementof the data vector by way of an XOR link.
 8. Method according to claim1, wherein: a) the key information vector is encrypted by means of asecond encryption method.
 9. A method for decryption of encrypted data,comprising: a) providing encrypted data, the encrypted data having beenencrypted by a method for the encryption of data including encryptingdata by: i) generating a key vector with a long second length from asecret key information vector with a short first length and a publicmatrix; and ii) forming an encryption vector from a data vector with athird length, which third length is shorter than or equal to the secondlength, and the key vector by means of a first encryption method; b)forming a key vector with a long second length from a key informationvector with a short first length and a public matrix; and c) forming adata vector with the long second length from an encryption vector withthe long second length and the key vector by means of the firstdecryption method.
 10. Method according to claim 9, wherein: a) thefirst decryption method corresponds to the first encryption method andcontains a link between the elements of the key vector and theencryption vector by way of an XOR link including the elements of thedata vector.
 11. A method for the encrypted transmission of data from atransmitter to a receiver, comprising: a) providing a transmitter whichgenerates encryption vectors from data vectors, a key information vectorand a public matrix by way of a method for the encryption of data, themethod including: i) generating a key vector with a long second lengthfrom a secret key information vector with a short first length and apublic matrix; ii) forming an encryption vector from a data vector witha third length, which third length is shorter than or equal to thesecond length, and the key vector by way of the first encryption method;b) sending the encryption vectors and the key information vector to areceiver; c) the receiver decrypting the encryption vectors from thepublic matrix and the key information vector by a method for decryptionof encrypted data, the method for decryption of encrypted dataincluding: i) providing encrypted data, the encrypted data having beenencrypted by a method for the encryption of data, including encryptingdata by: 1) generating a key vector with a long second length from asecret key information vector with a short first length and a publicmatrix; 2) forming an encryption vector from a data vector with a thirdlength, which third length is shorter than or equal to the secondlength, and the key vector by use of a first encryption method; 3)forming a key vector with a long second length from a key informationvector with a short first length and a public matrix; and 4) forming adata vector with the long second length from an encryption vector withthe long second length and the key vector by use of the first decryptionmethod.
 12. Method according to claim 11, wherein: a) the keyinformation vector is encrypted by the transmitter by use of a publickey; b) the encrypted key information vector is sent to the receiver,and c) the receiver obtains the key information vector from theencrypted key information vector by use of a private key from theencrypted key information signals.
 13. Method according to claim 11,wherein: a) the data vectors transmitted contain a second keyinformation vector that is used to calculate a new key by means of thepublic matrix in a subsequent encryption method of the transmitter anddecryption method of the receiver.
 14. Device for encryption of data,comprising: a) a key calculation device configured for calculating a keyvictor with a long second length from a key information vector with ashort first length and a matrix; b) a first encryption device configuredfor recording the key vector and a data vector with a third length, thethird length being less than or equal to the long length; c) the firstencryption device configured for supplying an encryption vector with thelong length; d) generating a key vector with a long second length from asecret key information vector with a short first length and a publicmatrix; and e) forming an encryption vector from a data vector with athird length, which third length is shorter than or equal to the secondlength, and the key vector by use of the first encryption method. 15.Device according to claim 14, further comprising: a) a second encryptiondevice configured for encrypting the key information vector is provided.16. Device according to claim 14, wherein: a) the first encryptiondevice includes a parallel computation device for the parallelcalculation of the elements of the key vector; and b) the firstencryption method is a symmetric encryption method in which the elementsof the key vector and the data vector are interlinked.
 17. Device fordecryption of encrypted data, comprising: a) a key calculation devicefor calculating the key vector with a long second length from a keyinformation vector with a short first length and a matrix; b) adecryption device for recording an encryption vector with the longlength and the key vector and for supplying a data vector with the longsecond length; c) the device forming a key vector with the long secondlength from a key information vector with the short first length and apublic matrix; and d) the device forming the data vector with the longsecond length from an encryption vector with the long second length andthe key vector by use of the first decryption method.
 18. Deviceaccording to claim 17, wherein: a) a second decryption device forrecording a encrypted key information vector and a private key and forsupplying the key information vector is provided.
 19. An encryptionsignal, comprising: a) at least one encryption vector; and b) the atleast one encryption vector having been generated by a method including:i) generating a key vector with a long second length from a secret keyinformation vector with a short first length and a public matrix; andii) forming an encryption vector from a data vector with a third length,which third length is shorter than or equal to the second length, andthe key vector by means of a first encryption method.
 20. Computerprogram, comprising: a) executing at least one of a method for theencryption of data and a method for the decryption of data; b) themethod for the encryption of data, comprising: i) generating a keyvector with a long second length from a secret key information vectorwith a short first length and a public matrix; and ii) forming anencryption vector from a data vector with a third length, which thirdlength is shorter than or equal to the second length, and the key vectorby means of a first encryption method; c) the method for the decryptionof data, including: i) providing encrypted data, the encrypted datahaving been encrypted by a method for the encryption of data includingencrypting data by: 1) generating a key vector with a long second lengthfrom a secret key information vector with a short first length and apublic matrix; 2) forming an encryption vector from a data vector with athird length, which third length is shorter than or equal to the secondlength, and the key vector by means of a first encryption method; ii)forming a key vector with a long second length from a key informationvector with a short first length and a public matrix; and iii) forming adata vector with the long second length from an encryption vector withthe long second length and the key vector by means of a first decryptionmethod.
 21. Computer-readable medium containing instructions forcontrolling a computer system to at least one of encrypt and decryptdata, by: a) executing at least one of a first group of instructions anda second group of instructions; b) the first group of instructionsincluding: i) generating a key vector with a long second length from asecret key information vector with a short first length and a publicmatrix; and ii) forming an encryption vector from a data vector with athird length, which third length is shorter than or equal to the secondlength, and the key vector by means of a first encryption method; c) thesecond group of instructions including: i) providing encrypted data, theencrypted data having been encrypted by a method for the encryption ofdata including encrypting data by: 1) generating a key vector with along second length from a secret key information vector with a shortfirst length and a public matrix; 2) forming an encryption vector from adata vector with a third length, which third length is shorter than orequal to the second length, and the key vector by means of a firstencryption method; and d) forming a key vector with a long second lengthfrom a key information vector with a short first length and a publicmatrix.
 22. Method according to claim 3, wherein: a) the large matrixvectors are identical and not equal to zero.
 23. Method according toclaim 1, wherein: a) the first encryption method includes a streamencryption method.
 24. Method according to claim 1, wherein: a) the keyinformation vector is encrypted by use of an asymmetric encryptionmethod.
 25. Method according to claim 24, wherein: a) the keyinformation vector is encrypted by use of an RSA method.
 26. Methodaccording to claim 11, wherein: a) the first decryption methodcorresponds to the first encryption method and contains a link betweenthe elements of the key vector and the encryption vector by way of anXOR link including the elements of the data vector.
 27. Method accordingto claim 26, wherein: a) the key information vector is encrypted by thetransmitter by use of an asymmetric encryption method.
 28. Deviceaccording to claim 15, wherein: a) the second encryption device encryptsthe key information vector by use of a public key.
 29. Device accordingto claim 17, wherein: a) the first decryption method corresponds to thefirst encryption method and contains a link between the elements of thekey vector and the encryption vector by way of an XOR link including theelements of the data vector.